Rotary regenerative heat exchanger

ABSTRACT

A rotary regenerative heat exchanger in which a disc-like matrix is rotated by providing circumferentially-spaced impulse buckets around the outer periphery of the matrix into which a nozzle is arranged to discharge a jet of fluid.

United States Patent 1191 Penny [4 Sept. 10, 1974 ROTARY REGENERATIVEHEAT [56] References Cited EXCHANGER UNITED STATES PATENTS [76]Inventor: Robert Noel Penny, l2 Alderbrook 3,007,685 11/1961 Hryniszak..165/7 X Rd., Solihull, England 3,203,181 8/1965 Benson 60/3951 H [22]Filed: 1972 Primary Examiner-Albert W. Davis, Jr. [21] App]. No.:313,881 Attorney, Agent, or Firm-Hauke, Gifford, Patalidis &

Dumont [30] Foreign Application Priority Data [57,] I ABSTRACT Dec. 18,1971 Great Britain 58898/71 A rotary regenerative heat exchanger inwhich a disc like matrix is rotated by providing circumferentially- [52]Cl 137 1 2; paced impulse buckets around the outer periphery of [51] IntCl Fzsd 19/00 I the matrix into which a nozzle is arranged to discharge58 Field of Search 165/7, 8, 10; 60/3951 H alet 5 Claims, 2 DrawingFigures ROTARY REGENERATIVE HEAT EXCHANGER The invention relates to arotary regenerative heat exchanger for a gas turbine engine and of thekind including a rotatable disc-like matrix having heat exchangepassages extending between the end faces of the matrix.

Hitherto such a matrix has been rotated either by mounting the matrixfor rotation by a co-axial shaft or by providing a driving annulusaround the outer periphery of the matrix. In either case the drivingmember, that is the shaft or annulus, would have to be driven throughgearing or other torque-transmitting means from an output shaft of thegasturbine engine with which the heat exchanger is associated. Thegearing may introduce several disadvantages, for example, increased costof manufacture, it occupies space adjacent the engine, and may introduceundesirable torque between the driving member and the matrix. An objectof the invention is to provide an alternative driving engagement whichdoes not require any torquetransmitting means outside the heatexchanger-housing.

According to the invention, a rotary regenerative heat exchanger havinga rotatable disc-like matrix having heat exchange passages extendingbetween the end faces of the matrix has a plurality of circumferentiallyspaced impulse buckets arranged around the outer periphery of thematrix, the heat exchanger also including means defining at least oneimpulse jet arranged to discharge fluid into the buckets thereby toeffect rotation of the matrix, sealing means being provided to preventleakage of fluid from the periphery of the matrix to the end facesthereof.

Preferably, the fluid supplied to the jets is derived from one of thefluid streams between which heat exchange is to be effected at aposition either upstream or downstream of the matrix, and the fluidafter leaving the buckets is returned to said fluid stream.

The buckets may be formed by recesses in the periphery of a rim portionof the matrix. Alternatively the periphery of the matrix may carryimpulse blading forming the aforesaid buckets.

The matrix may be mounted for rotation on a central shaft or axle or itmay be arranged to turn in a circular peripheral track or otherwise berestrained at its periphery for rotary movement.

By way of example, a rotaryregenerative heat exchanger of a gas turbineengine in accordance with the invention is now described with referenceto the accompanying drawings, in which:

FIG. 1 is an axial section through the heat exchanger, and

FIG. 2 is a section on the line IIII in FIG. 1.

The heat exchanger comprises housing parts 1, 2 defining a tubularhousing containing a disc-like matrix 3 rotatable co-axially in thehousing, walls 4, 5 dividing the housing into two substantiallysemi-cylindrical chambers 6, 7 and 8, 9 at each end of the matrix 3 andsupporting diametrically positioned bar-like seals 10, ll engaging therespective end faces of the matrix 3. The chambers 6, 7 and 8 leadcompressed air through the matrix 3 to a combustion chamber (not shown)of the engine and the chambers 9 and 7 lead exhaust gases from a turbine fnot shown) of theengin e to an exhaust duct. The matrix 3 has amultiplicity of passages therein for leading the compressed air and theexhaust gasesbetween the chambers 6 and 8 and 9 and 7 respectively. Thepassages may be defined between the convolutions of alternate corrugatedand plane strips of ceramic-like material spirally wound together beforefiring, as is well known, or through chambers defined between aperturedend plates and containing porous masses of heat exchange material.Whichever construction of matrix is employed, the porous part 12 of thematrix 13 is surrounded by a non-porous rim 13 which may be separatelymade or integral with the porous part 12. The rim 13 is located fromaxial movement in non-rotatable liners l4, 15 together defining anannular channel for receiving the rim l3 and themselves located in anannular channel defined by the housing parts 1, 2. The periphery of therim 13 of the matrix 3 is engaged by an enveloping ring formed byinterengaging arcuate blocks 16, 17 of two different materials, e.g., ametal and a ceramic. The blocks 16, conveniently those of metal, aresupported from the liners l4, 15 respectively by couplings 18 whichpermit limited radial and circumferential movement of the blocksrelatively to the liners. In this way relative expansion between thehousings parts 1, 2, the liners 14, 15, the ring of blocks 16, 17 andthe matrix 3 can be accommodated. The materials of the blocks 16 and 17and the arcuate lengths thereof are so chosen that the circumferentialexpansion of the composite ring approximates to that of the matrix 3.The material used for the liners 14, 15 is also selected to have acoefficient of expansion similar to that of the matrix material.

There is an annular gap between the inner peripheral wall of the linersl4, l5 and the outer periphery of the blocks 16, 17 forming an annularchamber 25 which communicates through passageways 19, 20 in the sealsl0, 11 with passageways 21, 22 in the walls 4, 5 and communicatingthrough ports 23, 24 with the compressed air chambers 6, 8. Thus theannular chamber 25 contains compressed air tapped from the compressedair stream passing through the matrix 3. One or two or more of theblocks 16, 17 are formed with impulse nozzles 26 for leading compressedair from the annular chamber25 to the periphery of the matrix 3. The rimportion of the matrix 3 is formed with bucketlike-depressions 27 ofsaw-tooth shape or scallops into which the nozzle or nozzles 26 directjets of compressed air. This effects rotation of the matrix 3. The speedof rotation can be altered by providing more or less nozzles 26 or bythe shape of the nozzles 26 or their inclination. The port 23communicating with the compressed air at the higher pressure end of thematrix 3 is larger than the port 24 to create a flow of compressed airinto the annular chamber 25. Compressed air from each depression 27communicates with the face of the liner adjacent the lower pressure endof the matrix 3, i.e., the right-hand end face as shown in FIG. 1,through a bleed duct 28 which when in registration with the seal 11 willleak round the back of the seal 11 into the passageway 22 and hencethrough the port 24 into the chamber 8. i

The illustrated embodiment provides a method of rotating the matrix at aspeed dependant upon the compressed air pressure and rate of flow.Furthermore no driving gear or equivalent means is required and noundesirable torque is produced in the matrix.

The illustrated embodiment may also be modified for the driving of ashaft-mounted matrix or a matrix freely mounted on an axle by providinga seal offset from and surrounding the matrix shaft and its bearingsinstead of using the diametrically-positioned bar seals 10, 11.

Instead of providing the depressions 27 in the rim of the matrix, thelatter may be provided with turbine blades to receive jets of compressedair from the nozzles 26.

Instead of the matrix being guided for rotary movement between thecomposite ring formed by the blocks l6, l7 and by the liners l4, 15, thematrix may be therwise restrained at its periphery, e.g., by three ormore circumferentially spaced rollers engaging the periphery of thematrix.

What I claim as my invention and desire to secure by Letters Patent ofthe United States is:

1. A rotary regenerative heat exchanger comprising v means defining atleast one impulse jet to discharge fluid into said buckets, thereby toeffect rotation of said matrix, and sealing means to prevent leakage ofsaid fluid from the periphery of said matrix to the end faces thereof. Y

2. A heat exchanger as claimed in claim 1 in which said fluid suppliedto said jets is derived from one of the fluid streams between which heatexchange is to be effected, said fluid after leaving the bucketsreturning to said fluid stream.

3. A heat exchanger as claimed in claim I in which said buckets areformed by recesses in the periphery of said matrix.

4. A heat exchanger as claimed in claim 1 including means defining acircular track in which the periphery of said matrix is arranged toturn.

5. A heat exchanger as claimed in claim 1 in which means are provided torestrain the matrix at its periphery for rotary movement.

UNITED STATES PATENT OFFICE v CERTIFICATE OF CORRECTION Patent NO. DatedSept.

Inventofl ROBERT N. PENNY It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Col. 1, line 62, delete the numeral "7" Col. 2, line 9, delete "13"first instance,

and insert 3- Signed and sealed this 5th day of November 1974.

(SEAL) Attest:

C. MARSHALL "DANN McCOY M. GIBSON JR.

Commissioner of Patents Attesting Officer RM P0405) uscoMM-oc some-poo.5. GDVIRNMINT PRINTING OFFICE 2 1." 0-366-334,

1. A rotary regenerative heat exchanger comprising a rotatable disc-likematrix having heat exchange passages extending between the end faces ofthe matrix, a plurality of circumferentiallyspaced impulse bucketsarranged around the outer periphery of said matrix, means defining atleast one impulse jet to discharge fluid into said buckets, thereby toeffect rotation of said matrix, and sealing means to prevent leakage ofsaid fluid from the periphery of said matrix to the end faces thereof.2. A heat exchanger as claimed in claim 1 in which said fluid suppliedto said jets is derived from one of the fluid streams between which heatexchange is to be effected, said fluid after leaving the bucketsreturning to said fluid stream.
 3. A heat exchanger as claimed in claim1 in which said buckets are formed by recesses in the periphery of saidmatrix.
 4. A heat exchanger as claimed in claim 1 including meansdefining a circular track in which the periphery of said matrix isarranged to turn.
 5. A heat exchanger as claimed in claim 1 in whichmeans are provided to restrain the matrix at its periphery for rotarymovement.